On Thursday, Hawaiian Electrical issued a long-awaited request for proposals (RFP) for about 900 megawatts of renewable vitality and vitality storage tasks. It’s the utility’s second main spherical of contracts prior to now 12 months looking for to marry variable photo voltaic and wind energy with the capability and suppleness of batteries.

However the Variable Renewable Dispatchable Era and Vitality Storage RFPs opened on Thursday are a bit extra sophisticated than their headline figures — looking for “applied sciences equal to 594 megawatts of photo voltaic for O‘ahu, 135 megawatts for Maui and as much as 203 megawatts for Hawai‘i Island” — would possibly point out.

In contrast to its first large solar-storage procurement in January, HECO’s new RFPs are damaged into a lot of particular tasks and particular wants throughout its three islands, with a mixture of completely different applied sciences required. This complexity comes from the truth that these RFPs have been structured to assist exchange two huge fossil fuel-fired energy crops to shut within the subsequent 5 years — the AES Hawaii coal-fired energy plant that serves about one-sixth of Oahu’s peak demand, set to retire in 2022, and the oil-fired Kahului plant on Maui, set to shut in 2024.

This impending lack of two huge spinning turbines has pushed HECO and regulators to approve a mix-and-match of know-how mixture to exchange them. That can make them onerous to match on to HECO’s first spherical of procurements, in addition to the utility-scale solar-plus-storage bids on the mainland.

Builders successful HECO’s first-round RFP in January shocked the business with costs starting from 12 cents per kilowatt-hour to a record-breaking eight cents per kilowatt-hour, as in comparison with common Hawaiian solar-storage undertaking costs of 11 cents per kilowatt-hour in 2017 and 13.9 cents per kilowatt-hour in 2016.

Additionally they got here with some novel constructions, akin to PPAs that changed funds primarily based on vitality deliveries to lump sums primarily based on internet vitality potential and availability, to make sure higher dispatchability for crucial hours of the day, Ravi Manghani, head of photo voltaic analysis for Wooden Mackenzie Energy & Renewables, famous.

A shift from solar-plus-storage to built-in grid planning

First, there’s a stand-alone storage part, with HECO looking for about 200 megawatts on Oahu and 40 megawatts on Maui, to “present capacity-like options to the respective island electrical grids.” Beneath the plan submitted to the Hawaii PUC in July, this capability was fast-tracked for supply to make sure it’s in place earlier than the ability crops shut.

Second, it features a separate name for customer-based “grid providers akin to quick frequency response and capability” for all three islands, in quantities starting from four megawatts on Hawaii to almost 120 megawatts on Oahu.

“It will create a chance for patrons to play a direct position in modernizing the electrical grid and integrating extra renewable vitality,” Thursday’s press announcement famous.

Most of those megawatts are within the type of multi-hour capability that may be served by conventional demand response, however HECO can be looking for a big share of ancillary providers that require split-second responsiveness from the masses or turbines concerned. HECO’s Built-in Demand Response Portfolio Plan, a long-running continuing meant to create markets to convey demand-side assets to bear as grid belongings, will information procurements on this monitor.

Lastly, Thursday’s RFP expands on the vary of providers that the “renewable dispatchable” era, which is able to make up the majority of the procurement, can present. As set out within the RFP tips, this era will possible encompass photo voltaic PV, or maybe wind or one other cost-competitive renewable useful resource, mixed with four-hour period batteries, to assist shift daytime peak photo voltaic manufacturing to cowl night peak buyer demand.

However past that, HECO can be opening up the chance for builders to tackle a “contingency storage” activity offering frequency response, so long as it’s not less than 5 megawatts and might function for half an hour. These are the identical traits of a whole lot of megawatts of batteries serving PJM’s frequency regulation market, they usually’re meant to serve an analogous position for HECO’s island grids.

HECO, which serves a few of the most PV-saturated neighborhoods within the nation, is already fighting voltage fluctuations, two-way energy flows, and different distribution grid disruptions that decision for a rise in a majority of these frequency regulation providers. And these issues will solely worsen in a long time to return, as Hawaii retires the massive spinning fossil fuel-fired turbines that present intertia and stability to the grid.

However photo voltaic farms will be operated in methods that may assist stability these grid frequency fluctuations, albeit not with out some marginal lack of vitality output. First Photo voltaic and California grid operator CAISO confirmed in a collection of pilot tasks that photo voltaic farms can use their inverters to mitigate frequency and voltage disruptions. Dedicating a portion of on-site vitality storage to frequency regulation may considerably increase that functionality.